The following relates generally to wireless communication, and more specifically to generating secondary synchronization signals for a synchronization channel in a cellular internet of things (CIoT) system.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems, (e.g., a Long Term Evolution (LTE) system). A wireless multiple-access communications system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE). Some of these UEs may be wireless devices that are part of a CIoT system, including those wireless devices implementing Machine-to-Machine (M2M) communication or Machine Type Communication (MTC).
Wireless devices in a CIoT system generally synchronize with another wireless device in order to communicate with that device. A synchronization channel, which may be transmitted periodically in a frame, may be used for such synchronization between the wireless devices. For example a base station, operating as a serving cell, may periodically transmit a synchronization channel that is intended for receipt by a UE that intends to synchronize with the base station. The UE may then determine synchronization information from the synchronization channel, for example to achieve frame, subframe, slot, and/or symbol synchronization with the base station. However, a wireless device attempting to detect a synchronization channel may misdetect a synchronization channel, for example where overlapping synchronization channel transmissions are received from neighboring wireless devices. For example, two neighboring base stations may transmit overlapping synchronization channels when received by the UE, resulting in a misdetection of all or a portion of the synchronization channel by the UE. Misdetection of all or portions of the synchronization channel may result in performance degradation, for example due to synchronization latency.